This invention relates to apparatus which facilitates the removal of a structure from a carrying vehicle and effects the support of that structure in a free standing position apart from the vehicle, thereby allowing the vehicle to be used independently thereof. The apparatus of the invention is particularly useful for a mobile camper unit normally transported on the bed of a pick-up truck, but may be equally employed on tractor-trailer units which transport for example shipping containers, or bulk fuel containers.
The wide spread use of small camping units which are detachable from the means of transportation, has brought about many different devices for lifting the structure from the vehicle to a free standing position and thereafter supporting the structure. However, these prior devices suffer a number of disadvantages which will be briefly discussed hereafter.
The most common method of separation and support of a conventional camper unit involves a use of jacks, either mechanically, or hydraulically actuated. Apart from the high cost of such apparatus, they in general provide a rather precarious support and are difficult to manage particularly when the supporting terrain is soft or sandy. In such cases, the jacks tend to sink under the weight of the camper thus rendering it substantially impossible to maintain the camper in a level, habitable condition. There is also a considerable amount of time wasted in setting up the camper, since with the conventional jacking systems, each jack has to be individually and in most cases manually adjusted.
Apparatus has also been devised which employs the power of the vehicle acting through inclined posts, or legs to raise a camper to its free standing position. One such device is the subject of U.S. Pat. No. 3,148,795 issued in 1964 to K. F. Leech.
This prior support arrangement has four stilt-like legs pivotally attached to mounting plates on each corner of the camper body, the lower ends of the legs defining the fulcrum by means of which the camper is raised or lowered. Apart from the obvious instability of this arrangement, the total weight of the camper and any uneven load application during use, causes extremely high stress levels to be generated at the area of each mounting plate and through the leg locking pins. The result being that continued torque applied at these points, causes metal fatigue, eventual breakage and possible collapse of the camper.
From devices of this nature, evolved the assembly disclosed by U.S. Pat. No. 3,715,100 issued 1973 to C. D. Spencer. This arrangement comprises a support rack for campers having pivotally interconnected parellelogram frames provided with locking devices and flexible frame holding means. These frames pivot within the limits of the holding means to move the camper on to and off a truck bed as the truck is moved, and the locks hold the camper substantially rigid, when in its elevated position.
While this arrangement provides a satisfactory support, it is a relatively complex structure which must be carried separately of the camper and assembled on site.